Analysis Of Clinical Characteristics Of Patients With Anti-NMDAR Encephalitis And Non-anti-NMDAR Encephalitis

BackgroundAutoimmune encephalitis(AE)is a type of encephalitis mediated by autoimmune mechanisms,accounting for 10%-20%of the total encephalitis.The disease involves a variety of self-antigens,most of which are encephalitis mediated by anti-cell surface antigens.Anti-cell surface antigen encephalitis can be divided into anti-NMDAR encephalitis,anti-LGI1 encephalitis,and anti-GABAR encephalitis,depending on the type of antibody.This classification method is conducive to indepth study of diseases from the perspective of antibodies,but has limited guiding value for clinical treatment.In order to guide clinical treatment and prognosis evaluation,it is more necessary to conduct cluster analysis from the mechanism level.The pathogenesis of AE can be divided into increased excitability and decreased inhibition.In this study,AEs were clustered according to this method,and anti-cell surface antigen encephalitis was divided into:anti-NMDAR encephalitis group with enhanced excitability,non-anti-NMDAR encephalitis group with weakened inhibition(anti-LGIl encephalitis,anti-GABABR encephalitis,anti-CASPR2 encephalitis,antiAMP AR encephalitis).By analyzing and comparing the clinical data of the two groups of encephalitis,the clinical characteristics of the two groups of patients were clarified,and the nodes requiring special attention were screened out.MethodsA total of 121 patients with positive autoimmune encephalitis-related antibodies who were admitted to the First Affiliated Hospital of Zhengzhou University from January 2020 to September 2021 were included and the patients were divided into anti-NMDAR encephalitis group and non-anti-NMDAR encephalitis group.The clinical data of patients were recorded in detail,such as gender composition,age of onset,length of hospital stay,proportion of intensive care unit(ICU)stay,ICU stay days,abnormal mental behavior,cognitive decline,seizures and treatment plan;and blood Complement,thyroid hormone levels,blood cytokines,lymphocyte subsets,and cerebrospinal fluid were examined and analyzed retrospectively.Statistical methods such as t-test,rank-sum test,χ2 test and Fisher’s exact test were used to analyze and compare the clinical data and various test indexes between anti-NMDAR encephalitis and non-anti-NMDAR encephalitis.ResultsAmong the 121 AE patients,62 patients(51.2%)had anti-NMDAR encephalitis;59 patients(48.8%)had non-anti-NMDAR encephalitis,including 23 patients with anti-LGI1 encephalitis and 20 patients with anti-GABABR antibody encephalitis,14 patients with anti-CASPR2 encephalitis,and 2 patients with anti-AMPAR encephalitis.Compared with the non-anti-NMDAR encephalitis group,the patients in the anti-NMDAR encephalitis group were younger[30(18-45)years old vs 60(47-65)years old,P<0.001];the proportion of abnormal mental behavior was higher[48 cases(77.4%)VS 23 cases(39.0%),P<0.001];the proportion of ICU admission was higher[29 cases(46.8%)VS 13 cases(22.0%),P=0.004];the length of stay in ICU was longer[17(11-32)days vs 8(4-14)days,P=0.006];longer hospital stay(24 ± 13 days vs 19±8 days,P=0.006).There were 107 patients with complete imaging data,including 56 patients in the anti-NMDAR encephalitis group and 51 in the non-anti-NMDAR encephalitis group.There was no significant difference in imaging changes between the two groups[32 cases(57.1%)vs 37 cases(72.5%),P=0.096].However,there were differences in the involved sites between the two groups.The anti-NMDAR encephalitis group was more likely to be involved in the thalamus and brainstem than the non-anti-NMDAR encephalitis group,respectively[6 cases(10.7%)VS 0 cases(0.0%),P=0.028;7 cases(12.5%)vs 0(0.1%),P=0.013].There was no significant difference between the anti-NMDAR encephalitis group and the non-anti-NMDAR encephalitis group in terms of needing anti-epileptic drug treatment(46 cases vs 41 cases);however,the number of patients requiring combined use of≥3 anti-epileptic drugs in the anti-NMDAR encephalitis group was significantly higher In the non-anti-NMDAR encephalitis group[26 cases(56.5%)vs 8 cases(19.5%),P<0.001].Compared with the non-anti-NMDAR encephalitis group,the anti-NMDAR encephalitis group had a higher cerebrospinal fluid white blood cell count[14.0(4.032.0)vs 2.0(2.0-6.0),P<0.001],a higher proportion of lymphocytes(P=0.011),chloride The chemical level was higher(P<0.001).The results of blood lymphocyte subset analysis showed that compared with the non-anti-NMDAR encephalitis group,the anti-NMDAR encephalitis group not only had a lower lymphocyte count[1211.49(894.20-1814.37)cells/uL VS 1864.00(1111.46-2287.88)cells/uL],P=0.037];and the counts of T and B lymphocytes in the subgroup were lower,respectively[764.51(635.10-1211.17)/uL VS 1237.00(713.61-1645.60)/uL,P=0.047],[208.81(141.07-377.71)/uL VS 238.00(200.00-332.00)/uL,P=0.005];both the count and percentage of helper T lymphocytes in T lymphocyte subsets decreased[398.96(290.06-591.15)/uL]VS 779.10(501.67-1088.00)/uL,P=0.006;(36.94±10.23)%VS(43.06±8.53)%,P=0.035].The results of blood cytokine analysis showed that there was no significant difference between the two groups in each index(P>0.05).Conclusion1.Compared with the non-anti-NMDAR encephalitis group,the anti-NMDAR encephalitis group was younger in age,had a higher proportion of abnormal mental behavior,and required a higher proportion of ICU admission due to severe illness and longer duration of hospitalization.≥3 antiepileptic drugs.2.Compared with the non-anti-NMDAR encephalitis group,the anti-NMDAR encephalitis group had stronger central nervous system inflammatory response and higher leukocytes in the cerebrospinal fluid.3.The immvine function of the patients in the anti-NMDAR encephalitis group was reduced,the cellular immunity and humoral immunity were lower than those of the non-anti-NMDAR encephalitis group,and the number and percentage of helper T lymphocytes were mainly decreased in the cellular immunity.